Concentrator for minerals in fine sized ranges



` July 3, 1951 T. s. BAILEY, JR 2,558,724

coNcENTRAToR FOR MINERALS 1N FINE sIzED RANGES Filed May 5, 1947 777007.95* 5I Bava/gf Jr'.

IN VEN TOR.

A 7' TOP/YEV Patented July 3, 1951 CONCENTRATOR FOR MINERALS IN FINE SIZED RANGES Thomas S. Bailey, Jr., Denver, Colo., assignor to Mining Process and Patent Company, Denver, Colo., a corporation of Delaware Application May 5, 1947, Serial No. 746,050

4 Claims.

This invention relates to concentration of minerals and more particularly relates to apparatus for the concentration of line-sized heavy minerals.

In many ore milling operations valuable minerals occur in such small percentage of the ore content that it is not economically feasible to recover such content by the usual ore dressing methods, such as froth otation or table concentration, for example.` Despite the economic complications, it frequently is desirable to recover such minerals due to their scarcity, as in the case of tin, or for other reasons.

It is an object of the present invention to provide simple, durable and eiicient apparatus for the concentration of low-grade ores and particularly adapted for the concentration of minerals in size ranges of from 150 to 1000 mesh.

Another object of this invention is to provide simple, economical and eilicient apparatus for concentrating low-grade ores which is capable of handling a relatively large tonnage with little Wear on the operating parts utilized in the treatment.

A further object of the invention is to provide simple, durable, and efficient apparatus which provides a relatively high ratio to concentration inthe treatment of low-grade minerals.

The present invention resides in the discovery that rigidized or relatively stiff metal sheets, if properly corrugated and arranged to be alternately tilted to opposed inclined positions will eectively trap a heavy mineral of an ore pulp owing across the corrugated surface in the series of recesses formed therein, and such mineral may be Washed from the metal surface during tilting in the opposite direction so as to separate such mineral from other constituents of the ore.

The practice of the present invention will be best understood by reference to the accompanying drawings. In the drawings, in the several views of which like parts have been designated similarly,

Fig. rl is a side elevation of concentrator apparatus embodying features of the present invention;

Fig. 2 is a fragmentary plan view of a portion of one of the decks shown in Fig. l, taken in the approximate position of the line 2-2, Fig. 1;

Fig. 3 is a fragmentary section taken approximately along the line 3 3, Fig. 2 across the table and direction of pulp flow; and

Fig. 4 is a fragmentary plan view, drawn to an enlarged scale, of the deck shown in Fig. 2.

As shown in Fig. 1, the concentrator C comprises a frame 5, on which a series of superposed decks 6 are mounted on pivot pins 'I for movement to oppositelyinclined positions, asindicated by the full line and dotted line representations. Tilting of the decks from one said position to the other is effected through the intermediary of a suitable motor M, speed reducer R, and transmission T, here shown as a chain and sprocket drive.

An ore pulp requiring concentration is fed through a feed distributor 8 by which it is selectively delivered onto one end of the respective decks B of the unit. Due to the inclination of these decks, the pulp ows from one end to the other of each deck during a predetermined period. In this action, the recesses 9 (Fig. 4) trap the heavy mineral tending to settle in the flow across the decks. 'I'he gangue discharging across the ends of the decks passes through a spout I0 to waste. As illustrated, the recesses have curved bottom portions and are substantially diamond shaped with the major axis transverse to the direction of W of material on the deck and with the minor axis parallel to said flow. Each side of the recess is dened by a ridge and the several recesses are in staggered relation so as to cause a zig-Zag travel of material along the surface of the deck, in which travel a substantial lateral )spreading is imparted to the material passing across the ridge dividing one recessed area from another.

Thereafter, the decks are tilted by the aforesaid mechanism to the dotted line positions shown in Fig. 1, While at the same time a Wash liquid, such as Water is delivered through header I2 and supply pipes I3, each provided with a series of apertures I4 so as to wash the decks 6 for removal of the entrapped mineral, which ultimately flows across the ends of said decks and eventually flows out of spout I5, Where it is collected or delivered to suitable treatment apparatus.

In order to demonstrate the effectiveness of the concentrating method just described, a series of comparative tests were undertaken, in which the same treatment was performed on the same material, except that the deck surface was changed for each series of tests.

In each case a 1000 gramy charge of ore was pulped to 20% solids and passed over the concentrator in 5 minutes. In one series of tests the decks were covered with rubber matting of conventional design. In the next series of tests, the decks Were covered with rigidized metal of the type shownk in Fig. 4. From the results obtained and from observations made during the tests, it is believed that the corrugated metal surface is superior to conventional rubber decks for the following reasons:

l. A higher grade of concentrate was produced -because the rubber surface tends to hold the gangue aswell as the'metallic sulphide. Y

2. A higher recovery was made because the rubber became saturated with gangue, and theY desired metallic sulphide was allowed to escape.

3. Mechanical manipulation 'in "washing the concentrate from the table was much fasterfand easier with the metal covering than with the rubber units.

4. Termination of the washing period may be positively determined with the metal Y surface whereas it was always questionable with the rubber surface.

'Ihe results of this comparative testing follow:

Test A Percent Product ggelg Pegg Rccggery Calculated Heads 100.00 0. 67 100.` 00 Concentrate 2. 90 17. 64 76. 67 Tailings 97. l 15 23. 33

CHECK TEST Calculated Heads 100.00 0.71 100.00 Concentrate 3.2 18. 03 80. 98 Tailings 96. 8 14 10. 02

Emmaus-Two 1000 gram charges of minus 100 mesh heads were passed over the Denver-Buckman tilting concentrator using the nietal decking and the above results were obtained. Direction of pulp flow was at right angles to the long'dimension of the indentations on the metal plate.

REMARKS.-Two 1000 gram charges of minus 100 mesh heads were passed over the Denver-Bucklnan tilting concentrator using thc standard rubber decking and the above results were obtained.

From the foregoing test operations, it will be apparent that there is a distinct advantage in the use of the metallic surfaces in the concentrator. However, for some purposes it may be desirableto employ more oi a` friction surface and this may be done by spraying the metal with a suitable rubber compound, by painting, or by applying an adhesive Ain which lint, hair or other materials may be embedded.

In the preferred arrangement, valve means are provided to control the iiow from header i2 into each of the distributors or supply pipes I3. When the ends of the decks carrying the supply pipes are in the down position, the valves remain closed and the pulp fed onto the deck at its opposite end flows down the deck by gravity. In this action, the heavier constituents, regardless of size, descend through the body of material andare trapped in the elongated recesses, while the lighter constituents discharge into spout I0.

After a given amount of feed has thus decended along the deck, the motor M and speed reducer R operate -'to tilt the 'deck in the opposite direction and at the same time the valves (not shown) open to allow a flow into the supply pipes I3 and through openings I4 onto the decks. This ow washes the mineral concentrate out of the recesses and on" the ends of the decks into Vthe receptacle l 5.

tions serves to effectively separate the valuable constituents from the gangue and is particularly .effective when the valuable constituents are present in size ranges ner than -150 mesh.

The present invention may be utilized in the Yconcentration of a variety of materials, as for STI example, wolframite, cassiterite, gold, scheelite, oxides, and tarnished materials. Typical applications of the use of the concentrator are low grade placer deposits, retreating tailings dumps, and increasing the efficiency of the slime section in gravity plants. Y

While the apparatus illustrated in the drawings represents a preferred structural arrangement, it will be understood that the deck surfaces may be arranged in a variety of ways to eiect the separation of heavy and lighter materials. Therefore, the description of such structural arrangement is not intended to limit the invention, but to explain the practice of the invention, the scope of which is defined in the hereunto appended claims.

What I claim and desire to secure by Letters Patent isz.l

1. In an ore concentrator, a material receiving decl; formed of a substantially stiff metal sheet, the upper surface of which has a series of shallow, substantially diamond-shaped recesses arranged in staggered sequence lengthwise of the deck with their major axes transverse to the flow of material along the deck and their minor axesparallel to said flow, each said recess being defined by a curved bottom portion sloping to ridges on each of its sides, each of which. ridges separates one recess from two adjoining recesses of the series, said deck being mounted for movement to oppositely inclined positions about a pivotal support, means for directing a wash liquid onto the elevated end of the deck in one position, and mechanism for tilting the deck.

2. In an ore concentrator, a material receiving deck formed ci substantially stiff metal sheet, the upper surface of which has a series of shallow. substantially diamond-shaped recesses arranged in staggered sequence lengthwise of the deck with their major axes transverse to the flow of the material along the deck and their minor axes parallel to said now, each said recess being dened by a curved bottom portion sloping upwardly to ridges on each of its sides, each of which ridges separates one recess from two adjoining recesses of the series, trunnion means for pivotally `supporting the deck for tilting movement about a horizontal axis, means for directing a wash liquid onto one end of the deck, and means for tilting the table about the trunnion means.

3. In an ore concentrator, a material receiving deckfformed of a substantially stili metal sheet, the upper surface of which has a series of sha1 low, substantially diamond-shaped recesses arranged in staggered sequence lengthwise of the deck with their major axes transverse to the flow of material along the deck and their minor axes parallel to said flow, each said recess being defined by a curved bottom portion sloping upwardly to ridges on each of its sides, each of which ridges separates one recess from two adjoining recesses of the series, a thin coating of organic material having a, high Icoefficient of friction on the metal surface, trunnion means for pivotally supporting the deck for tilting movement about a horizontal axis, means for directing a wash liquid onto one end of the table, and means for tilting the table about the trunnion means.`

4. In an cre concentrator, a material receiving deck formed of a substantially stiff metal sheet, the upper surface of which has a series of shallow, substantially diamond-shaped recesses arranged in staggered sequence lengthwise of the deck with their major axes transverse to the flow of material along the deck and their minor axes parallel to said flow, each said recess being dened by a curved bottom portion sloping upwardly to ridges on each of its sides, each of which ridges separates one rec-ess from two adjoining recesses of the series, said deck having pivotally supported near its mid-point for tilting movement about a horizontal axis to oppositely inclined positions, means for directing a Wash liquid onto one end of the deck, and means for tilting the deck about said horizontal axis. l THOMAS S. BAILEY, JR.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS lo Number Name Date 207,153 Bagley Aug. 20, 1878 652,900 Postlewaite July 3, 1900 760,214 Klein et al May 17, 1904 792,111 Barry June 1-3, 1905 1,007,074 Deister Oct. 31, '1911 1,007,075 Deister Oct. 31, 1911 1,010,350 eister Nov. 28, 1911 1,116,092 McIntire Nov. 3, 1914 1,534,536 Meyer Apr. 2l, 1925 1,541,246 Boylan June 9, 1925 2,138,313 Ulrich Nov. 29, 1938 2,373,931 Upham Apr. 17, 1945 FOREIGN PATENTS ,25 Number Country Date 104,119 Australia June 9, 1938 843,239 France Mar. 20, 1939 

1. IN AN ORE CONCENTRATOR, A MATERIAL RECEIVING DECK FORMED OF A SUBSTANTIALLY STIFF METAL SHEET, THE UPPER SURFACE OF WHICH HAS A SERIES OF SHALLOW, SUBSTANTIALLY DIAMOND-SHAPED RECESSES ARRANGED IN STAGGERED SEQUENCE LENGTHWISE OF THE DECK WITH THEIR MAJOR AXES TRANSVERSE TO THE FLOW OF MATERIAL ALONG THE DECK AND THIER MINOR AXES PARALLEL TO SAID FLOW, EACH SAID RECESS BEING DEFINED BY A CURVED BOTTOM PORTION SLOPING TO RIDGES ON EACH OF ITS SIDES, EACH OF WHICH RIDGES SEPARATES ONE RECESS FROM TWO ADJOINING RECESSES OF THE SERIES, SAID DECK BEING MOUNTED FOR MOVEMENT TO OPPOSITELY INCLINED POSITIONS ABOUT A PIVOTAL SUPPORT, MEANS FOR DIRECTING A WASH LIQUID ONTO THE ELEVATED END OF THE DECK IN ONE POSITION, AND MECHANISM FOR THE TILTING THE DECK. 